/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.sdk.nexmark.model.sql;



import com.bff.gaia.unified.sdk.coders.Coder;

import com.bff.gaia.unified.sdk.coders.CustomCoder;

import com.bff.gaia.unified.sdk.coders.RowCoder;

import com.bff.gaia.unified.sdk.coders.VarLongCoder;

import com.bff.gaia.unified.sdk.nexmark.model.KnownSize;

import com.bff.gaia.unified.sdk.transforms.DoFn;

import com.bff.gaia.unified.sdk.transforms.ParDo;

import com.bff.gaia.unified.sdk.values.Row;



import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;



/**

 * {@link KnownSize} implementation to estimate the size of a {@link Row}, similar to Java model.

 * NexmarkLauncher/Queries infrastructure expects the events to be able to quickly provide the

 * estimates of their sizes.

 *

 * <p>The {@link Row} size is calculated at creation time.

 */

public class RowSize implements KnownSize {

  private static final Coder<Long> LONG_CODER = VarLongCoder.of();

  public static final Coder<RowSize> CODER =

      new CustomCoder<RowSize>() {

        @Override

        public void encode(RowSize rowSize, OutputStream outStream) throws IOException {



          LONG_CODER.encode(rowSize.sizeInBytes(), outStream);

        }



        @Override

        public RowSize decode(InputStream inStream) throws IOException {

          return new RowSize(LONG_CODER.decode(inStream));

        }

      };



  public static ParDo.SingleOutput<Row, RowSize> parDo() {

    return ParDo.of(

        new DoFn<Row, RowSize>() {

          @ProcessElement

          public void processElement(ProcessContext c) {

            c.output(RowSize.of(c.element()));

          }

        });

  }



  public static RowSize of(Row row) {

    return new RowSize(sizeInBytes(row));

  }



  private static long sizeInBytes(Row row) {

    return RowCoder.estimatedSizeBytes(row);

  }



  private long sizeInBytes;



  private RowSize(long sizeInBytes) {

    this.sizeInBytes = sizeInBytes;

  }



  @Override

  public long sizeInBytes() {

    return sizeInBytes;

  }

}